1. Technical Field
The present invention relates to a liquid container in which a liquid such as ink is stored.
2. Related Art
Some of existing ink cartridges, a type of the liquid container, include a prism for detecting the amount of ink remaining in the cartridge on the basis of reflection status of light incident on the prism (see, for example, JP-A-2011-206936, pages 10 to 11 and FIG. 7). The prism is disposed in the container body such that a part of the prism is exposed through the lower face of the container body. Such an ink cartridge is normally mounted in an ink jet printer, and the ink stored in the main chamber of the ink cartridge is utilized for printing characters or images on a recording sheet.
In the thus-configured ink jet printer, the amount of ink in the ink cartridge is detected by emitting light to the prism located in a first sub chamber. Accordingly, when the ink in the first sub chamber runs out, it is decided that the ink in the ink cartridge has run out. In other words, the ink jet printer decides that the ink has run out despite the ink still remaining in a second sub chamber in the ink cartridge located downstream of the prism.
In the ink cartridge according to JP-A-2011-206936, the internal space of the container body in which the ink is stored is partitioned into the main chamber (including the first sub chamber) and the second sub chamber, and the volume of the second sub chamber located downstream from the prism is smaller than the volume of the main chamber upstream from the prism. Accordingly, the amount of the residual ink remaining in the internal space after the ink is decided to have run out can be reduced, compared with the case where the internal space in which the ink is stored is not partitioned into the main chamber and the second sub chamber. However, still there is a room for further improvement, since a small amount of ink does remain in the second sub chamber.